The invention relates to the winding of web materials about winding cores to form rolls of the materials, and the subsequent unwinding of the web materials from the rolls and splicing of a web tail end of a depleted roll to the web leading end of a new roll.
Web materials such as polymer film, paper, nonwoven or woven textile, metal foil, sheet metal, and others, are used in the manufacture of a variety of products. The web materials generally are provided in the form of large rolls formed by winding the web material about a winding core. To begin the winding process, a tail end of a web is attached to the winding core and the core is rotated about its axis to wind the web into a roll.
To manufacture products, the web material is unwound from the roll and subjected to converting operations, the particulars of which vary depending on the products being made. When the web from one roll is fully unwound, a splicing operation is performed wherein the leading end of the web from a new, full roll is attached to the tail end of the just-depleted roll, so that web material may be continuously supplied to the converting machinery.
Various approaches to the splicing of web material have been used, but the operation generally entails the use of some type of adhesive tape or substance for attaching the tail and leading ends of the webs together. If the adhesive were present on the tail end of a web prior to winding, the adhesive generally would have to face away from the core because that is the side of the web that will be brought into contact with the leading end of the new web to form the splice. Accordingly, the adhesive would stick to the subsequent turn of the web when the web is wound into a roll, which is clearly undesirable. Thus, some provision for preventing such sticking is necessary. U.S. Pat. No. 5,855,714 to Bockh proposes to overcome this difficulty by providing a non-adherable region on the tail end of the web adjacent the adhesive. The non-adherable region is long enough to extend at least one full turn about the core so that the adhesive is contacted by the non-adherable region and thereby is prevented from sticking. It may not be convenient or practical to form a non-adherable region on some types of web material, and in any event it would require a separate operation on the web prior to winding.
Additionally, mechanisms for splicing web materials generally have not aided or performed any function associated with the winding of the web into a roll.